Posted: 30 May 2019
The new C/AS2 covers the C clauses in the Building Code, and replaces the Acceptable Solutions C/AS2 to C/AS7. C/AS1 remains unchanged. The new C/AS2 will come into effect 27 June 2019, and has a transition period of four months.
Prior to 2012, there was one Acceptable Solution for fire, C/AS1. This document was then split up into seven Acceptable Solutions based on the risk group (or use) of the building. After receiving feedback from the sector, and holding various workshops across the country, six of the seven Acceptable Solutions are now being merged into one.
During public consultation, feedback was received from 38 organisations (private consultancies, government agencies, professional bodies, industry and research agencies) for the new C/AS2. In addition to the prescribed questions, an additional 700 comments were received on the Acceptable Solutions. Some of the proposed changes are considered technical changes that should be sent out for public consultation, and therefore could not be implemented in this upcoming edition. MBIE will review these and process them at a later stage. Where the changes were editorial, such as formatting or rewording to provide better clarification, these were incorporated where possible in the new C/AS2.
Key changes to performance settings
The majority of submissions supported the following technical changes:
- limiting the exemptions for sprinklers with dual water supply for unprotected openings in external wall areas within one metre of the boundary or where storage height is greater than three metres high (Section 5.2.2.a)
- simplifying the content in C/AS2 by referencing D1/AS1 – Access routes, rather than repeating the content from D/AS1
- adjusting building height demarcations for external wall cladding requirements from 7 to 10 metres to be consistent with the Building Code Clauses (Section 5.8.1)
- allowing full height group sleeping area partitions (Section 4.6.2)
- removal of a generic smoke control requirement for air handling system shutdowns (Section 4.18.1)
- setting the height restriction for balcony balustrades at 1100 mm minimum, not maximum, in line with F4/AS1 (Sections 3.11.5 and 3.11.6).
Additionally, there are numerous minor changes.
After considering sector feedback, MBIE did not adopt the proposed change to allow storage buildings to consider their intended storage versus the storage capacity, as this was thought too difficult to enforce.
Although there are new tables included to clarify requirements for fire safety, they are not a technical change. Key principles and settings that have historically been included in the Acceptable Solutions are unchanged, for example the travel distance measurement.
Education about the changes
MBIE will be hosting a webinar on 30 May with Local Government Zealand, and presenting at the Technical Series Seminar in June for the New Zealand Institute of Architects (NZIA). Another webinar will be held for fire engineers (SFPE) – this date is still being confirmed.
Thank you to all the submitters for taking the time to provide feedback; public consultation is important as it helps us shape the building regulatory system to support you and your industry.
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